This set of GIS Multiple Choice Questions & Answers (MCQs) focuses on “Commonly used Map Projections and their Comparison”.
1. What is used for navigation for maps of equatorial regions?
a) Transverse Mercator
b) Mercator
c) Oblique Mercator
d) Polyconic Projection
View Answer
Explanation: Distances are true only along equator in a Mercator. Distortion increases as distance increases from the equator and is extreme in Polar Regions.
2. Which map projection has true angles and shapes within any small area?
a) Polyconic Projection
b) Oblique Mercator
c) Mercator
d) Lambert Conical Orthomorphic Projection
View Answer
Explanation: Areas and shapes of large areas are distorted. Distortion is directly proportional to the distance from the equator. The map, however, is conformal in that angles and shapes within any small area (such as that shown by a USGS topographic map) are essentially true.
3. Which map projection is used for mapping large areas that are mainly extended in north-south direction?
a) Transverse Mercator
b) Mercator
c) Oblique Mercator
d) Polyconic Projection
View Answer
Explanation: Distances are true only along the central meridian selected by the map maker, or else along two lines parallel to it, and all distances, directions, shapes, and areas are reasonably accurate. Distortion of directions, distances and area increases outside the defined distance.
4. Which map projection is used by USGS for many quadrangle maps at scales from 1:24,000 to 1:250,000?
a) Oblique Mercator
b) Mercator
c) Transverse Mercator
d) Polyconic Projection
View Answer
Explanation: This projection is a transverse cylindrical case, in which the scale will be kept exact along the central meridian and along the equator. The mapped area may be extended without limit in the north-south direction.
5. The scale distortions are systematic and can be predetermined in a Transverse Mercator. Is this statement true or false?
a) True
b) False
View Answer
Explanation: Distortion of distances, directions, and size or area increases rapidly outside the defined distance. Graticule spacing increases away from central meridian.
6. Which map projection is used to show regions along a great circle other than the equator or a
Meridian?
a) Oblique Mercator
b) Mercator
c) Transverse Mercator
d) Polyconic Projection
View Answer
Explanation: These regions have their general extent oblique to the equator. This kind of map can be made to show as a straight line, the shortest distance between any two pre-selected points along the selected great circle. Distances are true only along the great circle or along two lines parallel to it.
7. In an Oblique Mercator, distortion is excessive toward the edges of a world map except near the path of the great circle. Is this statement true or false?
a) True
b) False
View Answer
Explanation: Distances, directions, areas, and shapes are fairly accurate within 15° of the great circle. Distortion of areas, distances, and shapes increases away from the great circle.
8. Which projections is used by Survey of India for making topographical maps of Scale 1:250,000 and more?
a) Lambert Conical Orthomorphic Projection
b) Mercator
c) Oblique Mercator
d) Polyconic Projection
View Answer
Explanation: Polyconic projection has generally been accepted as the best for a small, regular shaped area, such as, the standard quadrangle. It cannot be used on a large area without noticeable distortion.
9. Which type of projection portrays a portion of the earth’s surface on the developed surface of a secant cone?
a) Transverse Mercator
b) Mercator
c) Oblique Mercator
d) Lambert Conical Orthomorphic Projection
View Answer
Explanation: When using two standard parallels, in the area between these parallels, the map scale will be too small and in the area outside the parallels it will be too great.
10. In India which type of projection is used for creating geographical maps?
a) Mercator
b) Oblique Mercator
c) Lambert Conical Orthomorphic Projection
d) Polyconic Projection
View Answer
Explanation: Lambert conical orthomorphic projection is used along the parallel of latitude at orthomorphic projection with two standard parallels by countries having predominant east-west directions for topographical mapping. In India we use this projection for geographical maps.
Sanfoundry Global Education & Learning Series – GIS.
To practice all areas of GIS, here is complete set of Multiple Choice Questions and Answers.